make_chroot: drop python-3 unmerge logic

We've started shipping python-3 in the sdk, so don't unmerge it anymore.
We'll just waste time on developer's systems re-emerging it.

BUG=chromium:422771
TEST=`cros_sdk --chroot foo` doesn't remove/install python-3

Change-Id: Ie15228cfcf33987df4c909c48830eb591237eb55
Reviewed-on: https://chromium-review.googlesource.com/223164
Reviewed-by: Yu-Ju Hong <yjhong@chromium.org>
Commit-Queue: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
1 file changed